Pre-charged prophy angle

ABSTRACT

A prophy angle for storing prophy paste in a controlled releasable manner, the angle having a first drive mechanism comprising a drive shaft for delivering mechanical energy to a rotatable head assembly at a distal end of prophy angle and an independent second drive mechanism configured to deliver a controlled amount of paste from a chamber to the distal end of the prophy angle, the second drive mechanism comprising an index wheel engaging an actuator so that the wheel may be driven in a stepped rotational manner upon actuation of the actuator by the clinician.

BACKGROUND

The embodiments herein relate generally to a self-contained prophy angleemploying an effective delivery system for dispensing dentrifice in acontrolled and economical manner.

A prophy angle is a generally small hand-held device used by dentalclinicians to apply therapy to a patient, usually in the form ofspecially formulated prophy paste for teeth polishing. A rotating cup isoften detachably affixed to the distal tip of the prophy angle at anangle to the main longitudinal housing of the prophy angle. The proximalend of the prophy angle is configured as a handle so that the dentalclinician, such as a dental hygienist, can exert some comfortable forceto polish a patient's teeth with prophy paste applied to the cup.

Traditionally, prophy paste is manually applied to the cup prior to itsinsertion in the mouth, and then the cup applied to the patient's teethwhile power is applied to the device to rotate the cup at a fairly highspeed. In that regard, the proximal end of the prophy angle comprises ahousing with an opening for accepting therewithin, typically viafriction fit, a handle containing a drive mechanism. Historically, thedrive mechanism was powered by a tethered drive cable, but since thenthe drive mechanism comprises a pneumatically-driven motor powered by atethered air hose. The drive motor is conventionally configured toengage a drive shaft extending from the proximal end of the prophyangle. The drive shaft is axially positioned generally centrally withinthe prophy angle such that, at a distal end of the drive shaft, a set ofbevel gears is typically provided that, in turn, rotatably drive the cuppositioned at about an angle normal to the drive shaft.

Over the years, numerous configurations of prophy angles have beenpresented, with many never becoming commercialized. A prophy angle isintended to be a sturdy but generally light-weight device that isintended for single use only in an effort to address certain infectioncontrol issues in the dental practice. Certain bells and whistles havebeen suggested for the prophy angle over time, but one that has value,but has not yet been commercialized, is a pre-charged prophy angle;i.e., a prophy angle containing a chamber for storing prophy paste andmeans for discharging the paste as needed. In that regard, numerouspatents have been issued on the general scheme of a self-containedprophy angle, including U.S. Pat. No. 2,400,912 to Britt et al.; U.S.Pat. No. 3,389,468 to Lewis, U.S. Pat. No. 3,579,835 to Levenson, U.S.Pat. No. 3,769,707 to Condon, U.S. Pat. No. 3,775,849 to Condon, U.S.Pat. No. 3,987,550 to Danne et al., U.S. Pat. No. 4,220,446 to Walker,U.S. Pat. No. 4,266,933 to Warden et al., U.S. Pat. No. 5,062,796 toRosenberg, U.S. Pat. No. 5,208,933 to Lustig et al., U.S. Pat. No.5,642,994 to Chipian et al., U.S. Pat. No. 5,871,353 to Pierce et al.,U.S. Pat. No. 5,927,976 to Wu, U.S. Pat. No. 6,632,090 to Randolph, U.S.Pat. No. 7,070,412 to Stadeker, U.S. Pat. No. 7,101,182 to Garrison etal., U.S. Pat. No. 7,160,108 to Jaffe, U.S. Patent No. Appl. No.2009-0098505 to Randolph, and PCT Appl. No. WO2009-140630 to Bellanti.None have been known to be successfully commercialized, ostensiblybecause they are generally not clinically relevant, not cost effectiveor commercially viable.

By way of specific example, FIG. 1 herein reflects figures from the '912patent to Britt et al. The disclosed device includes a means of forcingthe paste from a chamber to a recess in the tool, which includes aplunger mounted for reciprocation in the chamber that engages the shelland has formed therein a central opening to accommodate the shaft andthe shell therearound. With the chamber filled with paste and theplunger in the retracted position, appropriate forward movement of theplunger forces the paste out through the tube and passages. Themechanism of action, as reflected by the arrangement of components inFIG. 1 herein, however, evidences a level of complexity that makesoperation inefficient and terribly cost inefficient to manufacture.

By way of an additional example, FIG. 2 herein reflects a figure fromthe '468 patent to Lewis. There, a housing is disclosed that ispre-charged with a quantity of paste prior to the insertion of a pistonwithin the housing. Rotation of the drive shaft in a direction formoving the piston toward the shoulder forces the paste within thechamber outwardly through the passageway and through the passageway intothe interior chamber of the prophy cup. Simultaneously the rotation ofthe drive shaft rotates the gear that, in turn, transmits rotation tothe cup. Among other limitations, the Lewis device suffers from a lackof control of paste discharge, as the action of discharge is controlledby the system driving rotation of the prophy cup. The other prior artprophy angles, even those containing a pre-charging feature, suffer fromsimilar limitations.

As such, a need has arisen for an effective and cost efficientpre-charged prophy angle to meet the dental treatment needs.

SUMMARY

In that regard, embodiments of the present invention satisfy that needby providing an improved self-contained prophy angle that hasindependent control over the advancement and discharge of prophy pasteor the like while simultaneously controlling rotating of the distalprophy cup or other working tool end. In one embodiment, a hand-heldoral hygiene applicator or prophy angle is provided comprising a prophyangle housing having a distal end and a proximal end, where the prophyangle housing is configured to permit the clinician to convenientlyhandle the prophy angle housing at the proximal end while the distal endis placed within a patient's mouth during use. The prophy angle housingis preferably configured to permit the clinician to simultaneouslycontrol the expression of paste while providing the desired treatment tothe patient.

In one embodiment, the prophy angle comprises a first drive mechanismpositioned within the prophy angle housing comprising a drive shaft fordelivering mechanical energy to a rotatable head assembly provided atthe distal end of the prophy angle housing; a chamber substantiallyenclosed within the prophy angle housing, the chamber configured tostore paste in a controlled releasable manner, the chamber beingconfigured to permit expression of paste by the clinician from theproximal end of the prophy angle housing; and an independent seconddrive mechanism provided within the prophy angle housing, the seconddrive mechanism configured to deliver a controlled amount of paste fromthe chamber to the distal end of the prophy angle housing for as neededexpression thereof to the patient by the clinician, the second drivemechanism comprising an actuator positioned at or proximate the proximalend of the prophy angle housing, an index wheel engaging the actuator sothat the wheel may be driven in a stepped rotational manner uponactuation of the actuator by the clinician, the index wheel furtherengaging a barrel within the reloadable chamber, the barrel axiallyexerting pressure against the paste within the chamber for delivering acontrolled quantity of paste toward the distal end of the prophy angle.

In one embodiment, the secondary drive mechanism comprises a shaftcomprising helical thread rotatably supporting the barrel, whereby thechamber and helical thread are sized to deliver a pre-set amount ofpaste for each actuation of the actuator. In another embodiment, thedrive shaft of the first drive mechanism is positioned co-linearly withthe helical thread and positioned therewithin. In yet anotherembodiment, the actuator comprises a finger press comprising a memberfor engaging the index wheel. If desired, the chamber may be configuredto be rechargeable for additional use.

BRIEF DESCRIPTION OF THE FIGURES

The detailed description of some embodiments of the invention will be ismade below with reference to the accompanying figures, wherein likenumerals represent corresponding parts of the figures.

FIG. 1 shows prior art figures from U.S. Pat. No. 2,400,912 to Britt etal.;

FIG. 2 shows a prior art figure from U.S. Pat. No. 3,389,468 to

Lewis;

FIG. 3 is a schematic perspective view of a first embodiment prophyangle;

FIG. 4 is a schematic cross-section elevational view of the embodimentof FIG. 3.

DETAILED DESCRIPTION OF CERTAIN EMBODIMENTS

By way of example, and referring to FIG. 3, one embodiment of thepresent invention is a hand-held oral hygiene applicator comprising aself-contained prophy angle 10 comprising a distal member 12 detachablyconnected to a proximal member 14. The distal member 12 comprises ahousing 16 having a proximal end 16 a and a distal end 16 b supporting arotatable head assembly or prophy cup 18. The cup 18 may be detachableor fixed to the housing. The proximal member 14 encloses a drivemechanism that is linked directly or indirectly to a power source (notshown). The proximal member 14 further functions to serve as a handlefor the dental clinician. The general size and shape may vary fromembodiment to embodiment, but it is preferred that the arrangement besuch that the prophy angle be configured to permit a user to grasp theproximal member 14 with the hand in a manner to permit an index fingeror thumb to be free to exert force upon the distal member 12 forcontrolled paste expression during use. It is important to note that theinvention herein may be used with any type of dentifrice or pastematerial having therapeutic or non- therapeutic application, dependingupon how the dental clinician intends to use embodiments of theinvention.

Referring to FIG. 4, the details of the distal member 12 may beappreciated. Provided at the distal end 16 b of housing 16 is the prophycup 18 comprising an internal chamber 20 for discharged paste toaccumulate during operation. The prophy cup 18 rotates based upon adrive system, which in one embodiment comprises a first bevel gear 22engaging a second bevel gear 24 secured to the distal end of a driveshaft 26 that extends axially through the distal member 12. In someembodiments, the drive shaft 26 extends into proximal member 14 by wayof friction fit engagement with the drive mechanism (not shown)positioned within the proximal member 14.

In one embodiment, the proximal member 14 is detachably engaged to thedistal member 12 via a friction fit, or alternatively within acorresponding connection means within the proximal end 16 a of distalmember housing 16. In either case, the connection should be made in amanner that the drive mechanism drives the drive shaft 26 so that theprophy cup 18 rotates for dental use. The particulars of the powersource and the drive mechanism for the rotating prophy cup are not thesubject of the present application. Indeed, one of the benefits ofcertain embodiments of the present invention is that the drive mechanismfor the rotating prophy cup is independent of the self-containedpaste-dispensing feature.

In that regard, one embodiment of the present invention comprises ascrew shaft 30 rotatably housed within a primary chamber 32 defined at aproximal end by a wall 34 and at the distal end by a tapered portion 36terminating in a distal wall 38. It should be noted that, although FIG.4 shows one embodiment generally in elevational cross-section, the screwshaft 30 itself is shown partially in cross-section (above the driveshaft 26) and partially from an external view (below the drive shaft 26)for greater clarity of its configuration in this particular embodiment.

The distal wall 38 partially defines a secondary chamber 40 surroundingthe drive shaft 26 a in a manner in which the drive shaft is protectedfrom contact with the paste by a surrounding wall. The secondary chamber40 is fluidly connected to an outlet conduit 42 leading to thedispensing chamber 20 of the prophy cup 18. The secondary chamber 40 andthe outlet conduit 42 are configured such that they are not structurallyimpacted by, and remain stationary during, rotation of the drive shaftand the prophy cup.

The screw shaft 30 comprises an external helical thread 46 positionedalong the distal portion of the shaft 30 that is positioned rotatablywithin primary chamber 32. At the distal portion of the screw shaft 30is a helical blade 48 that tapers conformingly within the taperedportion 36 of the housing 16. Surrounding the screw shaft is barrel 54configured to engage the external helical thread 46 of the shaft 30 witha mating internal helical thread 56. With such a configuration, rotationof the screw shaft 30 drives the barrel 54 distally forward in an axialmanner; i.e., toward the distal end 16 b of the distal member housing16. The barrel 54 is configured to conform to the internal preferablycylindrical profile of the primary chamber 32 so that any paste storedwithin the chamber 32 is forced distally (in a quasi stepped plungingaction) into the tapered portion 36 of the chamber where the helicalblade further drives the paste into the secondary chamber 40 fordischarge into the prophy cup chamber 20.

Rotation of the shaft 30 is driven in a controlled fashion by an indexwheel or gear 50 that may be indexed radially by manual trigger ofdispensing actuation means 60 secured to the proximal housing 16. In oneembodiment, the actuation means 60 comprises a finger press 62preferably ribbed for greater control and rotatably connected to thehousing 16 via hinge 64, and is suitable for use with the thumb or indexfinger. The finger press 62 comprises an extension member 66 thatengages at its distal end 68 the gear 50, which preferably has teeth orother indexing means so that depression of the finger press 62controllably rotates the screw shaft 30 a desired amount. Preferably,the configuration of the prophy angle 10 is designed so that a singleindexed radial advancement of the screw shaft by a single finger presscorresponds with the discharge of a sensible amount of paste for use bythe dental clinician. It need not do so, however, if it would be moredesired to express or dispense a smaller or larger quantity for eachmanual trigger of the actuation means 60.

It is contemplated that the prophy angle 10 be pre-charged with pasteduring the production process so that it is shipped in a ready-to-usestate. For example, the paste may be loaded into the primary chamber 32prior to placement of the barrel plunger 54 and proximal wall 34 intothe proximal end 16 a of the distal member housing 16, or through theconduit 42 at the distal end 16 b of the housing 16. Or a sealableopening may be provided in the proximal wall 34 or other location withinthe prophy angle proximal member 12 to permit injection of the pasteinto the chamber post-production, but prior to shipment. It is evencontemplated that the clinician might load the paste into the primarychamber prior to use. The prophy angle may be designed for single use,or multiple use in which appropriate cleaning and/or sterilizationmethods are employed.

In one embodiment of the present invention, the components of the prophyangle are manufactured using sturdy but light weight materials,including but not limited to lightweight metals, or thermoplastics suchas acrylonitrile butadiene styrene (ABS), polypropylene, polyethylene,polycarbonate or sturdy by lightweight material. However, othermaterials may be used. Indeed, alternative embodiments are contemplatedwithout departing from the spirit of the invention described and claimedherein. Each of the components may be configured differently toaccommodate a variety of sizes and arrangements while still maintainingthe independence of the discharge of paste from the prophy cup drivemechanism. For example, the distal housing 16 need not include a taperedportion. In another example, the actuation means 60 may comprise aconfiguration in which the user's finger may engage the gear 50 directlyto rotate the screw a set indexed amount. In yet another example, a lockmeans may be provided to preclude reverse direction of the screw shaft30. These examples are not intended to be limiting. As such, theinvention herein, as reflected by exemplary embodiments presented,should be measured by the claims set forth below.

1. A hand-held oral hygiene applicator for conveniently providing aclinician user the ability to express prophy paste while the applicatoris in therapeutic use within a patient's mouth, the applicatorcomprising: a prophy angle housing comprising a distal end and aproximal end, the prophy angle housing configured to permit theclinician to conveniently handle the prophy angle housing at theproximal end while the distal end is placed within a patient's mouthduring use, the prophy angle housing being further configured to permitthe clinician to simultaneously control the expression of paste whileproviding the desired treatment to the patient; a first drive mechanismpositioned within the prophy angle housing comprising a drive shaft fordelivering mechanical energy to a rotatable head assembly provided atthe distal end of the prophy angle housing; a chamber substantiallyenclosed within the prophy angle housing, the chamber configured tostore paste in a controlled releasable manner such that the paste is notin contact with the first drive mechanism, the chamber being configuredto permit expression of paste by the clinician from the proximal end ofthe prophy angle housing; and an independent second drive mechanismprovided within the prophy angle housing and positioned substantiallycoaxially with the first drive mechanism, the second drive mechanismconfigured to deliver a controlled amount of paste from the chamber tothe distal end of the prophy angle housing for as needed expressionthereof to the patient by the clinician, the second drive mechanismcomprising an actuator positioned at or proximate the proximal end ofthe prophy angle housing, an index wheel engaging the actuator so thatthe wheel may be driven in a stepped rotational manner upon actuation ofthe actuator by the clinician, the index wheel further engaging a barrelwithin the chamber, the barrel axially exerting pressure against thepaste within the chamber for delivering a controlled quantity of pastetoward the distal end of the prophy angle.
 2. The applicator of claim 1wherein the secondary drive mechanism comprises a shaft comprising ahelical thread rotatably supporting the barrel, whereby the chamber andhelical thread are sized to deliver a pre-set amount of paste for eachactuation of the actuator.
 3. The applicator of claim 2 wherein thedrive shaft of the first drive mechanism is positioned co-linearly withthe helical thread and positioned therewithin.
 4. The applicator ofclaim 1 wherein the chamber is configured to be rechargeable.
 5. Theapplicator of claim 1 wherein the actuator comprises a finger presscomprising a member for engaging the index wheel.